To the north west of the Caithness town of Thurso, close to the seashore, sits a few confused grassy rubble mounds. These are all that remain of the ancient
Scrabster castle or the 'Palace' of the Bishop's of Caithness, first recorded in 1328. The site appears to have had a keep a lean-to hall block with kitchens, a low surrounding courtyard wall and possibly a gatehouse on the landward side. In 1544,Scrabster was seized by the Sinclairs, Earls of Caithness of Girnigoe castle for unclear reasons. But likely to stop Alexander Gordon, son of the Earl of Sunderland from taking hold of the castle as temporary Bishop and
turning the site into a Gordon interest. By as early as 1726 the castle was totally ruinous.

Today the seaward side of the castle is marked by a World War II concrete pill box, while the landward side is highlighted by a ditch and stream. Which at one time if dammed
back could provided a reasonable moat to defend the castle's landward approach and must have been spanned by a wooden drawbridge. The reconstruction shows the castle as it may have appeared from the sea with the courtyard wall running back to the main keep seized by the Sinclairs in 1544.